NAME    [Toc]    [Back]

     hardclock - real-time timer

SYNOPSIS    [Toc]    [Back]

     void
     hardclock(struct clockframe *);

DESCRIPTION    [Toc]    [Back]

     The hardclock() function gets called hz(9) times per second.  It performs
     different tasks:
     +o   Run the current process's virtual and profile time (decrease the corresponding
 timers, if they are activated, and generate SIGVTALRM or
         SIGPROF, respectively).
     +o   Increment the time-of-day, taking care of any ntpd(8) or adjtime(2)
         induced changes and leap seconds, as well as any necessary compensations
 to keep in sync with PPS signals or external clocks, if support
         for this is in the kernel (see options(4)).
     +o   Schedule softclock interrupts if any callouts should be triggered
         (see callout(9)).

SEE ALSO    [Toc]    [Back]

     adjtime(2), ntp_adjtime(2), signal(7), ntpd(8), callout(9), hz(9)

BSD                            September 5, 2001                           BSD